ref: dca4cd41d41545175457d49a180a12064b804d3b
dir: femtolisp/llt/operators.c
#include <limits.h>
#include <assert.h>
#include "dtypes.h"
#include "utils.h"
#include "ieee754.h"
// given a number, determine an appropriate type for storing it
#if 0
numerictype_t effective_numerictype(double r)
{
double fp;
fp = fpart(r);
if (fp != 0 || r > U64_MAX || r < S64_MIN) {
if (r > FLT_MAX || r < -FLT_MAX || (fabs(r) < FLT_MIN)) {
return T_DOUBLE;
}
else {
return T_FLOAT;
}
}
else if (r >= SCHAR_MIN && r <= SCHAR_MAX) {
return T_INT8;
}
else if (r >= SHRT_MIN && r <= SHRT_MAX) {
return T_INT16;
}
else if (r >= INT_MIN && r <= INT_MAX) {
return T_INT32;
}
else if (r <= S64_MAX) {
return T_INT64;
}
return T_UINT64;
}
#else
// simpler version implementing a smaller preferred type repertoire
numerictype_t effective_numerictype(double r)
{
double fp;
fp = fpart(r);
if (fp != 0 || r > U64_MAX || r < S64_MIN) {
return T_DOUBLE;
}
else if (r >= INT_MIN && r <= INT_MAX) {
return T_INT32;
}
else if (r <= S64_MAX) {
return T_INT64;
}
return T_UINT64;
}
#endif
double conv_to_double(void *data, numerictype_t tag)
{
double d=0;
switch (tag) {
case T_INT8: d = (double)*(int8_t*)data; break;
case T_UINT8: d = (double)*(uint8_t*)data; break;
case T_INT16: d = (double)*(int16_t*)data; break;
case T_UINT16: d = (double)*(uint16_t*)data; break;
case T_INT32: d = (double)*(int32_t*)data; break;
case T_UINT32: d = (double)*(uint32_t*)data; break;
case T_INT64:
d = (double)*(int64_t*)data;
if (d > 0 && *(int64_t*)data < 0) // can happen!
d = -d;
break;
case T_UINT64: d = (double)*(uint64_t*)data; break;
case T_FLOAT: d = (double)*(float*)data; break;
case T_DOUBLE: return *(double*)data;
}
return d;
}
void conv_from_double(void *dest, double d, numerictype_t tag)
{
switch (tag) {
case T_INT8: *(int8_t*)dest = d; break;
case T_UINT8: *(uint8_t*)dest = d; break;
case T_INT16: *(int16_t*)dest = d; break;
case T_UINT16: *(uint16_t*)dest = d; break;
case T_INT32: *(int32_t*)dest = d; break;
case T_UINT32: *(uint32_t*)dest = d; break;
case T_INT64:
*(int64_t*)dest = d;
if (d > 0 && *(int64_t*)dest < 0) // 0x8000000000000000 is a bitch
*(int64_t*)dest = S64_MAX;
break;
case T_UINT64: *(uint64_t*)dest = (int64_t)d; break;
case T_FLOAT: *(float*)dest = d; break;
case T_DOUBLE: *(double*)dest = d; break;
}
}
#define CONV_TO_INTTYPE(type) \
type##_t conv_to_##type(void *data, numerictype_t tag) \
{ \
type##_t i=0; \
switch (tag) { \
case T_INT8: i = (type##_t)*(int8_t*)data; break; \
case T_UINT8: i = (type##_t)*(uint8_t*)data; break; \
case T_INT16: i = (type##_t)*(int16_t*)data; break; \
case T_UINT16: i = (type##_t)*(uint16_t*)data; break; \
case T_INT32: i = (type##_t)*(int32_t*)data; break; \
case T_UINT32: i = (type##_t)*(uint32_t*)data; break; \
case T_INT64: i = (type##_t)*(int64_t*)data; break; \
case T_UINT64: i = (type##_t)*(uint64_t*)data; break; \
case T_FLOAT: i = (type##_t)*(float*)data; break; \
case T_DOUBLE: i = (type##_t)*(double*)data; break; \
} \
return i; \
}
CONV_TO_INTTYPE(int64)
CONV_TO_INTTYPE(int32)
CONV_TO_INTTYPE(uint32)
// this is needed to work around a possible compiler bug
// casting negative floats and doubles to uint64. you need
// to cast to int64 first.
uint64_t conv_to_uint64(void *data, numerictype_t tag)
{
uint64_t i=0;
switch (tag) {
case T_INT8: i = (uint64_t)*(int8_t*)data; break;
case T_UINT8: i = (uint64_t)*(uint8_t*)data; break;
case T_INT16: i = (uint64_t)*(int16_t*)data; break;
case T_UINT16: i = (uint64_t)*(uint16_t*)data; break;
case T_INT32: i = (uint64_t)*(int32_t*)data; break;
case T_UINT32: i = (uint64_t)*(uint32_t*)data; break;
case T_INT64: i = (uint64_t)*(int64_t*)data; break;
case T_UINT64: i = (uint64_t)*(uint64_t*)data; break;
case T_FLOAT:
if (*(float*)data >= 0)
i = (uint64_t)*(float*)data;
else
i = (uint64_t)(int64_t)*(float*)data;
break;
case T_DOUBLE:
if (*(double*)data >= 0)
i = (uint64_t)*(double*)data;
else
i = (uint64_t)(int64_t)*(double*)data;
break;
}
return i;
}
int cmp_same_lt(void *a, void *b, numerictype_t tag)
{
switch (tag) {
case T_INT8: return *(int8_t*)a < *(int8_t*)b;
case T_UINT8: return *(uint8_t*)a < *(uint8_t*)b;
case T_INT16: return *(int16_t*)a < *(int16_t*)b;
case T_UINT16: return *(uint16_t*)a < *(uint16_t*)b;
case T_INT32: return *(int32_t*)a < *(int32_t*)b;
case T_UINT32: return *(uint32_t*)a < *(uint32_t*)b;
case T_INT64: return *(int64_t*)a < *(int64_t*)b;
case T_UINT64: return *(uint64_t*)a < *(uint64_t*)b;
case T_FLOAT: return *(float*)a < *(float*)b;
case T_DOUBLE: return *(double*)a < *(double*)b;
}
return 0;
}
int cmp_same_eq(void *a, void *b, numerictype_t tag)
{
switch (tag) {
case T_INT8: return *(int8_t*)a == *(int8_t*)b;
case T_UINT8: return *(uint8_t*)a == *(uint8_t*)b;
case T_INT16: return *(int16_t*)a == *(int16_t*)b;
case T_UINT16: return *(uint16_t*)a == *(uint16_t*)b;
case T_INT32: return *(int32_t*)a == *(int32_t*)b;
case T_UINT32: return *(uint32_t*)a == *(uint32_t*)b;
case T_INT64: return *(int64_t*)a == *(int64_t*)b;
case T_UINT64: return *(uint64_t*)a == *(uint64_t*)b;
case T_FLOAT: return *(float*)a == *(float*)b;
case T_DOUBLE: return *(double*)a == *(double*)b;
}
return 0;
}
int cmp_lt(void *a, numerictype_t atag, void *b, numerictype_t btag)
{
if (atag==btag)
return cmp_same_lt(a, b, atag);
double da = conv_to_double(a, atag);
double db = conv_to_double(b, btag);
// casting to double will only get the wrong answer for big int64s
// that differ in low bits
if (da < db)
return 1;
if (db < da)
return 0;
if (atag == T_UINT64) {
// this is safe because if a had been bigger than S64_MAX,
// we would already have concluded that it's bigger than b.
if (btag == T_INT64) {
return ((int64_t)*(uint64_t*)a < *(int64_t*)b);
}
else if (btag == T_DOUBLE) {
if (db != db) return 0;
return (*(uint64_t*)a < (uint64_t)*(double*)b);
}
}
else if (atag == T_INT64) {
if (btag == T_UINT64) {
return (*(int64_t*)a < (int64_t)*(uint64_t*)b);
}
else if (btag == T_DOUBLE) {
if (db != db) return 0;
return (*(int64_t*)a < (int64_t)*(double*)b);
}
}
else if (btag == T_UINT64) {
if (atag == T_INT64) {
return ((int64_t)*(uint64_t*)b > *(int64_t*)a);
}
else if (atag == T_DOUBLE) {
if (da != da) return 0;
return (*(uint64_t*)b > (uint64_t)*(double*)a);
}
}
else if (btag == T_INT64) {
if (atag == T_UINT64) {
return (*(int64_t*)b > (int64_t)*(uint64_t*)a);
}
else if (atag == T_DOUBLE) {
if (da != da) return 0;
return (*(int64_t*)b > (int64_t)*(double*)a);
}
}
return 0;
}
int cmp_eq(void *a, numerictype_t atag, void *b, numerictype_t btag,
int equalnans)
{
if (atag==btag && (!equalnans || atag < T_FLOAT))
return cmp_same_eq(a, b, atag);
double da = conv_to_double(a, atag);
double db = conv_to_double(b, btag);
if ((int)atag >= T_FLOAT && (int)btag >= T_FLOAT) {
if (equalnans) {
return *(uint64_t*)&da == *(uint64_t*)&db;
}
return (da == db);
}
if (da != db)
return 0;
if (atag == T_UINT64) {
// this is safe because if a had been bigger than S64_MAX,
// we would already have concluded that it's bigger than b.
if (btag == T_INT64) {
return ((int64_t)*(uint64_t*)a == *(int64_t*)b);
}
else if (btag == T_DOUBLE) {
return (*(uint64_t*)a == (uint64_t)(int64_t)*(double*)b);
}
}
else if (atag == T_INT64) {
if (btag == T_UINT64) {
return (*(int64_t*)a == (int64_t)*(uint64_t*)b);
}
else if (btag == T_DOUBLE) {
return (*(int64_t*)a == (int64_t)*(double*)b);
}
}
else if (btag == T_UINT64) {
if (atag == T_INT64) {
return ((int64_t)*(uint64_t*)b == *(int64_t*)a);
}
else if (atag == T_DOUBLE) {
return (*(uint64_t*)b == (uint64_t)(int64_t)*(double*)a);
}
}
else if (btag == T_INT64) {
if (atag == T_UINT64) {
return (*(int64_t*)b == (int64_t)*(uint64_t*)a);
}
else if (atag == T_DOUBLE) {
return (*(int64_t*)b == (int64_t)*(double*)a);
}
}
return 1;
}
#ifdef ENABLE_LLT_TEST
void test_operators()
{
int8_t i8, i8b;
uint8_t ui8, ui8b;
int16_t i16, i16b;
uint16_t ui16, ui16b;
int32_t i32, i32b;
uint32_t ui32, ui32b;
int64_t i64, i64b;
uint64_t ui64, ui64b;
float f, fb;
double d, db;
ui64 = U64_MAX;
ui64b = U64_MAX-1;
i64 = S64_MIN;
i64b = i64+1;
d = (double)ui64;
db = (double)i64b;
assert(cmp_lt(&i64, T_INT64, &ui64, T_UINT64));
assert(!cmp_lt(&ui64, T_UINT64, &i64, T_INT64));
assert(cmp_lt(&i64, T_INT64, &ui64b, T_UINT64));
assert(!cmp_lt(&ui64b, T_UINT64, &i64, T_INT64));
assert(cmp_lt(&i64, T_INT64, &i64b, T_INT64));
assert(!cmp_lt(&i64b, T_INT64, &i64, T_INT64));
// try to compare a double too big to fit in an int64 with an
// int64 requiring too much precision to fit in a double...
// this case fails but it's very difficult/expensive to support
//assert(cmp_lt(&ui64b, T_UINT64, &d, T_DOUBLE));
i64 = S64_MAX;
ui64 = S64_MAX-1;
assert(cmp_lt(&ui64, T_UINT64, &i64, T_INT64));
assert(!cmp_lt(&i64, T_INT64, &ui64, T_UINT64));
i64 = S64_MAX-1;
ui64 = S64_MAX;
assert(cmp_lt(&i64, T_INT64, &ui64, T_UINT64));
assert(!cmp_lt(&ui64, T_UINT64, &i64, T_INT64));
d = DBL_MAXINT;
i64 = DBL_MAXINT+100;
assert(cmp_lt(&d, T_DOUBLE, &i64, T_INT64));
assert(!cmp_lt(&i64, T_INT64, &d, T_DOUBLE));
i64 = DBL_MAXINT+10;
assert(cmp_lt(&d, T_DOUBLE, &i64, T_INT64));
assert(!cmp_lt(&i64, T_INT64, &d, T_DOUBLE));
i64 = DBL_MAXINT+1;
assert(cmp_lt(&d, T_DOUBLE, &i64, T_INT64));
assert(!cmp_lt(&i64, T_INT64, &d, T_DOUBLE));
assert(!cmp_eq(&d, T_DOUBLE, &i64, T_INT64, 0));
i64 = DBL_MAXINT;
assert(cmp_eq(&d, T_DOUBLE, &i64, T_INT64, 0));
}
#endif